well, he won't be changing out his supercharger unless he wants to do a ridiculously expensive mp112 build, the genV m90 that he has will be more than enough for most people. there's plenty of info on the site, just remember that most people have the earlier gen III supercharger. it's less efficient than the genV, and i've read that a 3.4 pulley on a genIII is about equal to a 3.6" pulley on a genV. keep that in mind as you read.
that being said, tell him to NOT simply drop pulley sizes. if you're familiar with knock retard, you'll understand why. i'll post the most helpful links at the bottom of this post.
short answer is that the easiest/cheapest/most common setup you'll see involves headers, an intake around the 4" variety, autolite 104 spark plugs (or equivalent, 1 heat range colder than stock), a 180* thermostat, a good tune, and a 3.6" supercharger pulley. best advice is to remember that there's more air coming in with a smaller pulley, so it has to come out somewhere. flow mods and temperature control (like porting) are key.
http://www.grandprixforums.net/f81/s...car-17482.html
http://www.grandprixforums.net/f18/w...here-1507.html
happy reading
